For years mechanics used a long pipe around one end of a wrench to increase leverage. This would sometimes be difficult because of the size of some open end wrenches. Prior devices have been patented for increasing the mechanical advantage of user of a wrench. These devices are design having two oppositely positioned U or V shaped members near one end of the handle, for receiving the wrench. The devices referred to is described in U.S. Pat. No. 4,960,014 by Kelley 81/177.2 and U.S. Pat. No. 4,644,600 by Fugate 81/177.2.
Mechanics have also used the pipe method to increase the torque applied to a ratchet handle. The devices patented in the category EXTENDIBLE TOOL HANDLE refers to ratchets having an extendible handle to allow the user to increase the leverage and torque applied to a tool headpiece or sockets. U.S. Pat. No. 4,581,958 by Shull 81/177.2 and U.S. Pat. No. 5,285,702 by Hilliguar 81,177.2. The devices in category EXTENSION HANDLE FOR WRENCHES and EXTENDIBLE TOOL HANDLE are not design to be used universally. Often mechanics need extensions that are extendible and can be used with wrenches ratchet handles, tire irons etc.